Flat-plate loop heat conduction device and manufacturing method thereof

ABSTRACT

A flat-plate loop heat conduction device and a manufacturing method thereof. The flat-plate loop heat conduction device includes an upper flat plate and a lower flat plate overlapping and mating with each other. Complementary partial evaporation sections, partial vapor transfer pipes, partial condensing sections and partial condensing transfer pipes are disposed on the upper and lower flat plates. After the upper and lower flat plates are mated with each other, a complete evaporation section, a complete condensing section, a complete vapor transfer pipe and a complete condensing transfer pipe are formed in communication with each other to achieve a heat conduction loop structure for a working fluid to circulate therein. The flat-plate loop heat conduction device is easier to manufacture. Moreover, the flat-plate loop heat conduction device has reinforced structure and is not subject to damage.

BACKGROUND OF THE INVENTION

The present invention relates generally to a heat conduction device, andmore particularly to a flat-plate loop heat conduction device and amanufacturing method thereof.

It is known that loop heat pipe is a heat dissipation device oftenapplied to various electronic components, notebook computers, LEDlighting systems, televisions, mechanical equipments, etc.

FIG. 1 shows a conventional loop heat pipe structure 10 including anevaporation section 12 with internal capillary structure, a compensationchamber 14 and a condensing section 16 arranged on a metal board. Thesecomponents are connected with vapor transfer pipe 17 and condensingtransfer pipe 18 to form a closed loop structure within which a workingfluid flows. The evaporation section 12 serves to absorb heattransferred from a heat source. The working fluid in the evaporationsection 12 will absorb the heat and phase-change into vapor. The vaporis transferred through the vapor transfer pipe 17 to the condensingsection 16. In the condensing section 16, the working fluid is condensedand phase-changed back into liquid. Then the capillary structure of theevaporation section 12 applies capillary attraction to the liquid,whereby the liquid flows back into the evaporation section 12 tocomplete a circulation loop.

The conventional loop heat pipe 10 has very fine structure so that it ishard to mass-produce such loop heat pipe 10. Moreover, the evaporationsection 12, the vapor transfer pipe 17 and the condensing transfer pipe18 are generally positioned outside the metal board of the condensingsection 16. That is, only the condensing section 16 is supported by themetal board 161, while other components are not supported by any supportstructure. As a result, the structure is not rigid enough as a whole.Therefore, when installing the loop heat pipe into an electronic deviceor uninstalling the loop heat pipe therefrom, an operator must be verycareful so as not to damage the loop heat pipe.

SUMMARY OF THE INVENTION

It is therefore a primary object of the present invention to provide aflat-plate loop heat conduction device and a manufacturing methodthereof. The flat-plate loop heat conduction device is composed of atleast two flat plates overlapping and mating with each other. Theflat-plate loop heat conduction device has simplified structure and iseasier to manufacture.

To achieve the above and other objects, the flat-plate loop heatconduction device of the present invention includes an upper flat plateand a lower flat plate overlapping and mating with each other.Complementary partial evaporation sections, partial vapor transferpipes, partial condensing sections and partial condensing transfer pipesare disposed on the mating faces of the upper and lower flat plates. Thepartial vapor transfer pipes are respectively connected to one end ofthe partial evaporation section and one end of the partial condensingsection. The partial condensing transfer pipes are respectivelyconnected to the other end of the partial evaporation section and theother end of the partial condensing section. Capillary structures aredisposed on inner surfaces of the partial evaporation sections and thepartial condensing transfer pipes of the upper and lower flat plates.After the upper and lower flat plates are mated with each other, acomplete evaporation section, a complete condensing section, a completevapor transfer pipe and a complete condensing transfer pipe are formedin communication with each other to achieve a loop structure withinwhich a working fluid can circulate.

The manufacturing method of the flat-plate loop heat conduction deviceof the present invention includes steps of: preparing an upper flatplate and a lower flat plate; forming complementary partial evaporationsections, partial vapor transfer pipes, partial condensing sections andpartial condensing transfer pipe on the upper and lower flat plates bymeans of etching, electroplating or laser processing, the partial vaportransfer pipes being respectively connected to one end of the partialevaporation sections and one end of the partial condensing sections, thepartial condensing transfer pipes being respectively connected to theother end of the partial evaporation sections and the other end of thepartial condensing sections, capillary structures being formed on innersurfaces of the partial evaporation sections and the partial condensingtransfer pipes by means of die-casting, etching, electroplating or laserprocessing; and mating the upper and lower flat plates with each otherto form a complete evaporation section, a complete condensing section, acomplete vapor transfer pipe and a complete condensing transfer pipebetween the mating faces of the upper and lower flat plates incommunication with each other, whereby a loop structure is achieved fora working fluid to circulate therewithin.

The present invention can be best understood through the followingdescription and accompanying drawings wherein:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a conventional loop heat pipe;

FIG. 2 is a perspective assembled view of the flat-plate loop heatconduction device of the present invention;

FIG. 3 is a perspective exploded view of the flat-plate loop heatconduction device of the present invention;

FIG. 4 is a sectional view of the flat-plate loop heat conduction deviceof the present invention;

FIG. 5 is a sectional view taken along line A-A of FIG. 4, showing thecapillary structures formed on the inner surface of the evaporationsection;

FIG. 6 is a sectional view taken along line B-B of FIG. 4, showing thecapillary structures formed on the inner surface of the winding passage;and

FIG. 7 is a flow chart of the manufacturing method of the flat-plateloop heat conduction device of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer to FIG. 2, which is a perspective view of the flat-plateloop heat conduction device of the present invention. The flat-plateloop heat conduction device 20 includes an upper flat plate 22 and alower flat plate 24. The thickness of the upper and lower flat plates22, 24 ranges from 0.05 cm to 20 cm. The upper and lower flat plates 22,24 can be made of metal, alloy or ceramic material.

Please refer to FIG. 3, which shows the structures of the upper andlower flat plates 22, 24. The upper and lower flat plates 22, 24respectively have complementary partial evaporation sections 261, 262,partial vapor transfer pipes 281, 282, partial condensing sections 301,302 and partial condensing transfer pipes 321, 322. The inlet ends 2810,2820 and outlet ends 2811, 2821 of the partial vapor transfer pipes 281,282 are respectively connected to the outlet ends 2611, 2621 of thepartial evaporation sections 261, 262 and the inlet ends 3010, 3020 ofthe partial condensing sections 301, 302. The inlet ends 3210, 3220 ofthe partial condensing transfer pipes 321, 322 are respectivelyconnected to the outlet ends 3011, 3021 of the partial condensingsections 301, 302 and the inlet ends 2610, 2620 of the partialevaporation sections 261, 262. In addition, partial winding passages341, 342 are arranged in the partial condensing sections 301, 302. Twoends of the partial winding passages 341, 342, that is, the inlet end3010 and the outlet end 3011, are respectively connected to the partialvapor transfer pipes 281, 282 and the inlet ends 3210, 3220 of thepartial condensing transfer pipes 321, 322. The other parts of the flatplates 22, 24 are flat sealingly connected sections 23, 25.

According to the above arrangement, when the upper and lower flat plates22, 24 are mated with and attached to each other as shown in FIG. 2, acomplete flat-plate loop heat conduction device 20 is achieved. In theflat-plate loop heat conduction device 20 are formed a completeevaporation section 26, a complete vapor transfer pipe 28, a completecondensing section 30, a complete condensing transfer pipe 32 and acomplete winding passage 34. Accordingly, a working fluid can circulatewithin the flat-plate loop heat conduction device 20 for heat exchangeas shown in FIG. 2.

Please further refer to FIGS. 4, 5 and 6. On the upper and lower flatplates 22, 24, capillary structures 38 are disposed on inner surfaces ofthe partial evaporation sections 261, 262, the partial condensingtransfer pipes 321, 322 and the partial winding passages 341, 342 of thepartial condensing sections 301, 302. FIGS. 5 and 6 are sectional viewstaken along line A-A and line B-B of FIG. 4, showing the capillarystructures of the evaporation section 26 and the winding passage 34 ofthe condensing section 30. The capillary structures 38 are formed withmultiple channels or filled with sintered metal powder or ceramicpowder. Alternatively, the capillary structures 38 are meshed texture orany other suitable porous structure for achieving capillarity.

When the evaporation section 26 absorbs the heat transferred from theheat source, the working fluid in the evaporation section 26 will absorbthe heat and phase-change into vapor phase. The vapor-phase workingfluid flows through the vapor transfer pipe 28 into the condensingsection 30. Thereafter, the vapor-phase working fluid is condensed andphase-changed back into liquid-phase working fluid. Then the internalcapillary structures of the condensing section 30, the condensingtransfer pipe 32 and the evaporation section 26 apply capillaryattraction to the liquid-phase working fluid. Accordingly, theliquid-phase working fluid quickly flows back to the evaporation section26 to complete a circulation loop and achieve heat dissipation effect.

The present invention includes at least one evaporation section 26 andat least one condensing section. The number of the evaporation section26 can be increased according to the requirement of the heat source. Inthis case, one condensing section 30 is for multiple evaporationsections 26. Multiple radiating fins (not shown) can be disposed at thecondensing section 30 to enhance condensing effect.

Please now refer to FIG. 7, which is a flow chart of the manufacturingmethod of the flat-plate loop heat conduction device of the presentinvention. The method includes steps S1, S2, and S3. In step S1, atleast two flat plates are prepared, that is, an upper flat plate and alower flat plate. By means of etching, electroplating or laserprocessing, the upper and lower flat plates are formed withcomplementary partial evaporation sections, partial vapor transferpipes, partial condensing sections and partial condensing transferpipes. Complementary partial winding passages are arranged in thepartial condensing sections. The partial winding passages can becombined into a complete winding passage. The partial vapor transferpipes are respectively connected to first ends of the partialevaporation sections and the partial condensing sections. The partialcondensing transfer pipes are respectively connected to second ends ofthe partial evaporation sections and the partial condensing sections.Two ends of the partial winding passages are respectively connected tothe partial vapor transfer pipes and the partial condensing transferpipes. In step S2, by means of die-casting, etching, electroplating orlaser processing, capillary structures are formed on inner surfaces ofthe partial evaporation sections, the partial condensing transfer pipesand the partial winding passages. The capillary structures are formedwith multiple channels or filled with sintered metal powder or ceramicpowder. Alternatively, the capillary structures are formed of any othersuitable porous material. Finally, in step S3, by means of thermalultrasonic welding, laser sealing or metal/nonmetal adhesion, the upperand lower flat plates are mated with each other to form a completeflat-plate loop heat conduction device. In the flat-plate loop heatconduction device are formed a complete evaporation section, a completecondensing section, a complete vapor transfer pipe, a completecondensing transfer pipe and a complete winding passage in communicationwith each other. A working fluid can circulate within the flat-plateloop heat conduction device. In order to enhance the condensing effectof the condensing section, multiple radiating fins can be disposed atthe condensing section.

Alternatively, the flat-plate loop heat conduction device can includethree or more flat plates, which are connected with each other to formthe complete circulation loop.

According to the above arrangement, the heat conduction structure of thepresent invention is composed of at least two flat plates. Thisfacilitates processing and reduces difficulty in manufacturing of thecapillary structures. Accordingly, the present invention can be moreeasily manufactured.

The above embodiments are only used to illustrate the present invention,not intended to limit the scope thereof. Many modifications of the aboveembodiments can be made without departing from the spirit of the presentinvention.

1. A flat-plate loop heat conduction device at least comprising an upperflat plate and a lower flat plate overlapping and mating with eachother, on a mating face of at least one of the upper and lower flatplates being disposed at least one partial evaporation section, onepartial vapor transfer pipe, one partial condensing section and onepartial condensing transfer pipe, two ends of the partial vapor transferpipe being respectively connected to one end of the partial evaporationsection and one end of the partial condensing section, two ends of thepartial condensing transfer pipe being respectively connected to theother end of the partial evaporation section and the other end of thepartial condensing section, whereby after the upper and lower flatplates are mated with each other, a complete evaporation section, acomplete condensing section, a complete vapor transfer pipe and acomplete condensing transfer pipe are formed between the mating faces ofthe upper and lower flat plates in communication with each other toachieve a loop structure within which a working fluid can circulate. 2.The flat-plate loop heat conduction device as claimed in claim 1,wherein complementary partial winding passages are arranged in thepartial condensing sections of the upper and lower flat plates, two endsof the partial winding passages being respectively connected to thepartial vapor transfer pipes and the partial condensing transfer pipes,capillary structures being disposed on inner surfaces of the partialwinding passages.
 3. The flat-plate loop heat conduction device asclaimed in claim 1, wherein capillary structures are disposed on innersurfaces of at least one of the evaporation section, the condensingsection, the vapor transfer pipe and the condensing transfer pipe. 4.The flat-plate loop heat conduction device as claimed in claim 2,wherein capillary structures are disposed on inner surfaces of at leastone of the evaporation section, the condensing section, the vaportransfer pipe and the condensing transfer pipe.
 5. The flat-plate loopheat conduction device as claimed in claim 3, wherein the capillarystructures are formed with multiple channels.
 6. The flat-plate loopheat conduction device as claimed in claim 3, wherein the capillarystructures are filled with sintered metal powder or ceramic powder toform porous structures.
 7. The flat-plate loop heat conduction device asclaimed in claim 1, wherein there are multiple evaporation sections andone condensing section.
 8. The flat-plate loop heat conduction device asclaimed in claim 2, wherein there are multiple evaporation sections andone condensing section.
 9. The flat-plate loop heat conduction device asclaimed in claim 3, wherein there are multiple evaporation sections andone condensing section.
 10. The flat-plate loop heat conduction deviceas claimed in claim 1, wherein the upper and lower flat plates have athickness ranging from 0.05 cm to 20 cm.
 11. The flat-plate loop heatconduction device as claimed in claim 2, wherein the upper and lowerflat plates have a thickness ranging from 0.05 cm to 20 cm.
 12. Theflat-plate loop heat conduction device as claimed in claim 3, whereinthe upper and lower flat plates have a thickness ranging from 0.05 cm to20 cm.
 13. The flat-plate loop heat conduction device as claimed inclaim 7, wherein the upper and lower flat plates have a thicknessranging from 0.05 cm to 20 cm.
 14. The flat-plate loop heat conductiondevice as claimed in claim 1, wherein the upper and lower flat platesare made of at least one of the following materials: metal, alloy,ceramic material and silicon.
 15. The flat-plate loop heat conductiondevice as claimed in claim 2, wherein the upper and lower flat platesare made of at least one of the following materials: metal, alloy,ceramic material and silicon.
 16. The flat-plate loop heat conductiondevice as claimed in claim 3, wherein the upper and lower flat platesare made of at least one of the following materials: metal, alloy,ceramic material and silicon.
 17. The flat-plate loop heat conductiondevice as claimed in claim 1, wherein radiating fins are disposed at thecondensing section.
 18. The flat-plate loop heat conduction device asclaimed in claim 2, wherein radiating fins are disposed at thecondensing section.
 19. The flat-plate loop heat conduction device asclaimed in claim 3, wherein radiating fins are disposed at thecondensing section.
 20. The flat-plate loop heat conduction device asclaimed in claim 10, wherein radiating fins are disposed at thecondensing section.
 21. A manufacturing method of a flat-plate loop heatconduction device, comprising steps of: preparing an upper flat plateand a lower flat plate; forming complementary partial evaporationsections, partial vapor transfer pipes, partial condensing sections andpartial condensing transfer pipe on mating faces of the upper and lowerflat plates respectively, two ends of the partial vapor transfer pipesbeing respectively connected to one end of the partial evaporationsections and one end of the partial condensing sections, two ends of thepartial condensing transfer pipes being respectively connected to theother end of the partial evaporation sections and the other end of thepartial condensing sections; and mating the upper and lower flat plateswith each other to form a complete evaporation section, a completecondensing section, a complete vapor transfer pipe and a completecondensing transfer pipe between the mating faces of the upper and lowerflat plates in communication with each other, whereby a loop structureis achieved for a working fluid to circulate therewithin.
 22. Themanufacturing method of the flat-plate loop heat conduction device asclaimed in claim 19, wherein complementary partial winding passages arearranged in the partial condensing sections of the upper and lower flatplates, two ends of the partial winding passages being respectivelyconnected to the partial vapor transfer pipes and the partial condensingtransfer pipes.
 23. The manufacturing method of the flat-plate loop heatconduction device as claimed in claim 21, wherein capillary structuresare disposed on inner surfaces of at least one of the evaporationsection, the condensing section, the vapor transfer pipe and thecondensing transfer pipe.
 24. The manufacturing method of the flat-plateloop heat conduction device as claimed in claim 23, wherein thecapillary structures are formed with multiple channels.
 25. Themanufacturing method of the flat-plate loop heat conduction device asclaimed in claim 23, wherein before mating the upper and lower flatplates with each other, the capillary structures are filled withsintered metal powder or ceramic powder to form porous structures. 26.The manufacturing method of the flat-plate loop heat conduction deviceas claimed in claim 24, wherein the capillary structures are filled withsintered metal powder or ceramic powder to form porous structures. 27.The manufacturing method of the flat-plate loop heat conduction deviceas claimed in claim 23, wherein the capillary structures are formed bymeans of die-casting, etching, electroplating or laser processing. 28.The manufacturing method of the flat-plate loop heat conduction deviceas claimed in claim 25, wherein the capillary structures are formed bymeans of die-casting, etching, electroplating or laser processing. 29.The manufacturing method of the flat-plate loop heat conduction deviceas claimed in claim 21, wherein the upper and lower flat plates aremated with each other by means of thermal ultrasonic welding, lasersealing or metal/nonmetal adhesion.
 30. The manufacturing method of theflat-plate loop heat conduction device as claimed in claim 22, whereinthe upper and lower flat plates are mated with each other by means ofthermal ultrasonic welding, laser sealing or metal/nonmetal adhesion 31.The manufacturing method of the flat-plate loop heat conduction deviceas claimed in claim 23, wherein the upper and lower flat plates aremated with each other by means of thermal ultrasonic welding, lasersealing or metal/nonmetal adhesion.
 32. The manufacturing method of theflat-plate loop heat conduction device as claimed in claim 25, whereinthe upper and lower flat plates are mated with each other by means ofthermal ultrasonic welding, laser sealing or metal/nonmetal adhesion.33. The manufacturing method of the flat-plate loop heat conductiondevice as claimed in claim 27, wherein the upper and lower flat platesare mated with each other by means of thermal ultrasonic welding, lasersealing or metal/nonmetal adhesion.
 34. The manufacturing method of theflat-plate loop heat conduction device as claimed in claim 21, whereinthe upper and lower flat plates have a thickness ranging from 0.05 cm to20 cm.
 35. The manufacturing method of the flat-plate loop heatconduction device as claimed in claim 22, wherein the upper and lowerflat plates have a thickness ranging from 0.05 cm to 20 cm.
 36. Themanufacturing method of the flat-plate loop heat conduction device asclaimed in claim 23, wherein the upper and lower flat plates have athickness ranging from 0.05 cm to 20 cm.
 37. The manufacturing method ofthe flat-plate loop heat conduction device as claimed in claim 21,wherein the upper and lower flat plates are made of at least one of thefollowing materials: metal, alloy, ceramic material and silicon.
 38. Themanufacturing method of the flat-plate loop heat conduction device asclaimed in claim 22, wherein the upper and lower flat plates are made ofat least one of the following materials: metal, alloy, ceramic materialand silicon.
 39. The manufacturing method of the flat-plate loop heatconduction device as claimed in claim 23, wherein the upper and lowerflat plates are made of at least one of the following materials: metal,alloy, ceramic material and silicon.
 40. The manufacturing method of theflat-plate loop heat conduction device as claimed in claim 25, whereinthe upper and lower flat plates are made of at least one of thefollowing materials: metal, alloy, ceramic material and silicon.
 41. Themanufacturing method of the flat-plate loop heat conduction device asclaimed in claim 27, wherein the upper and lower flat plates are made ofat least one of the following materials: metal, alloy, ceramic materialand silicon.
 42. The manufacturing method of the flat-plate loop heatconduction device as claimed in claim 28, wherein the upper and lowerflat plates are made of at least one of the following materials: metal,alloy, ceramic material and silicon.
 43. The manufacturing method of theflat-plate loop heat conduction device as claimed in claim 21, whereinradiating fins are disposed at the condensing section.
 44. Themanufacturing method of the flat-plate loop heat conduction device asclaimed in claim 22, wherein radiating fins are disposed at thecondensing section.
 45. The manufacturing method of the flat-plate loopheat conduction device as claimed in claim 23, wherein radiating finsare disposed at the condensing section.
 46. The manufacturing method ofthe flat-plate loop heat conduction device as claimed in claim 25,wherein radiating fins are disposed at the condensing section.
 47. Themanufacturing method of the flat-plate loop heat conduction device asclaimed in claim 27, wherein radiating fins are disposed at thecondensing section.
 48. The manufacturing method of the flat-plate loopheat conduction device as claimed in claim 28, wherein radiating finsare disposed at the condensing section.